Isolation and characterization of heat-responsive gene TaGASR1 from wheat (Triticum aestivum L.)

GA-stimulated transcript (GAST) family genes have been identified in numerous plant species. In this paper, we isolated and characterized a heat-responsive gene, TaGASR1 , from heat tolerant variety TAM107. The complete ORF of TaGASR1 was cloned, which encoded a 98-kDa protein, and the sequence shared 51.52% similarity to OsGASR1 . Analysis of the TaGASR1 promoter region showed that it contained a heat shock element (HSE) and several cis -elements involved in abiotic stress response and hormone signal transduction. Expression patterns of TaGASR1 revealed that it was strongly induced by stress factors, such as high temperature, drought, high salinity and oxidation, as well as the phytohormones, including MeJA, ACC and ABA, which suggested the TaGASR1 gene might participate in these stress and hormone signal transduction pathways. Transient expression of TaGASR1-GFP fusion proteins in onion epidermal cells indicated that TaGASR1 protein was localized to the cell membrane or cytosol. Further analysis showed that ectopic expression of TaGASR1 in Arabidopsis enhanced thermotolerance and reduced the accumulation of reactive oxygen species (ROS) after heat stress. Moreover, we also found that TaGASR1 -overexpressing wheat improved tolerance to heat stress and oxidative stress.